Int. J. Med. Sci. 2005 2
70
International Journal of Medical Sciences
ISSN 1449-1907 www.medsci.org 2005 2(2):70-78
©2005 Ivyspring International Publisher. All rights reserved
Study of urban community survey in India: growing trend of
high prevalence of hypertension in a developing country
Research paper

Received: 2004.09.01
Accepted: 2005.02.10
Published: 2005.04.01
Shyamal Kumar Das
1
, Kalyan Sanyal
2
, Arindam Basu
3

1 Dept Of Neuromedicine, Bangur Institute Of Neurology, Kolkata, India.
2 Malda District Hospital, Malda, India.
3 Fogarty Training Program, IPGMER, Kolkata, India.
A
A
b
b
s
s
t
t
r

relationship of hypertension with age, sedentary occupation, body mass
index (BMI), diet, ischemic heart disease, and smoking. Multivariate analysis
revealed age and BMI as risk factors, and non-vegetarian diet as protective
factor with respect to hypertension. Prevalence of prehypertensives was high
among younger subjects - particularly students and laborers who need special
attention. Role of non-vegetarian diet as a protective factor might have been
related to fish-eating behavior of the sample population, who also use
mustard oil as cooking medium - both of which have significant level of
essential polyunsaturated fatty acids. The observed prevalence of
hypertension in this study and other studies suggest the need for a
comprehensive national policy to control hypertension in India, and, in other
similar developing countries.
K
K
e
e
y
yw
w
o
o
r
r
d
d
s
s

p
p
h
h
y
yShyamal Kumar Das is the professor of neuromedicine at Bangur Institute of Neurology at
the Institute of Postgraduate Medical Education and Research, Kolkata, India. He is also the
chief of movement disorders clinic at the Bangur Institute of Neurology at Kolkata, India.
Prof Das obtained his MD and superspecialty training in Neurology from the Postgraduate
Institute of Medical Education and Research, Chandigarh, India between 1982-1985. He did a
fellowship in movement disorders at the University of Calgary, Canada, between 1996-1997.
He has numerous publications in leading international journals on Internal Medicine and
Neuromedicine. His primary research interests include neuroepidemiology and movement
disorders.
…Continued at the end of paper.
C
C
o
o
r
r
r
r
e
e
s
s
Dr. Shyamal Kumar Das, Q No.- 74, Minto Park Govt. Housing estate, 247/1, A J C Bose
road, Kolkata-700027. E-mail: [email protected]

Int. J. Med. Sci. 2005 2
71
1. BACKGROUND
An epidemiological shift in the prevalence of hypertension in developing countries as compared to developed countries has
been observed [1,2]. Studies from India and Bangladesh have shown upward trend in the prevalence of hypertension [3]. India is a
vast country with a heterogeneous and young population. Till recent past, control and prevention of communicable diseases was
emphasized. Recently, attention has shifted to control and prevention of non-communicable diseases including stroke, hypertension
and coronary artery disease at the national level in view of the rising trends. Community surveys from different regions and various
ethnic populations are instrumental to formulate national consensus-driven policies to counteract the rising trend of non-
communicable diseases. The prevalence of hypertension has increased by 30 times among the urban population over a period of 55
years and about 10 times among the rural population over a period of 36 years [4]. Various hypotheses have been put forward to
explain this rising trend and among these, consequences of urbanization such as change in life style pattern, diet and stress have been
implicated. The current urbanization rate in India is 35% as compared to 15% in the 1950. With growing urbanization, socio-
developmental changes have taken place over last 40-50 years. Dramatic changes in life style from traditional to modern have lead
to physical inactivity due to technological advances. Rising affluence has modified the dietary pattern characterized by increased
consumption of diets rich in fat, sugar and calories. Furthermore, increasing population growth at the current rate of about 2% in
each year and technological advances have shrunken the employment opportunities particularly among young generation – leading
to stress and hypertension in young persons, including students and laborers. The primary objective of this project was to study the
prevalence of hypertension in an urban population in West Bengal- an eastern state of India - using the recently published “The
Seventh Report Of Joint National committee on Prevention, Detection, Evaluation and Treatment of High blood Pressure (JNC-VII)
criteria” [5]. Additionally, the study aimed to identify the various risk factors for hypertension with the purpose to suggest possible
interventions based on the risk factor analysis.
2. METHODOLOGY
Place of survey and the population
Malda, a district town in the state of West Bengal, had been the place of survey. Demographic characteristic of the sample

All participants above 40 years underwent electrocardiograms (ECG), irrespective of level of blood pressure. Participants who
were below 40 years of age, only those who had hypertension and complained of typical precordial pain suggestive of ischemic heart
disease, had ECGs. Participants with typical central chest pain, suggestive ECG changes and on anti ischemic drugs are considered
to be suffering from myocardial ischemia. Salt intake was assessed from the amount of salt used in cooking and extra salt used
during meal.
Statistical Analysis
We used EPI-INFO-2002 software for data entry and analysis. We applied chi-square test to find out the results at 5%
significance for the select risk factors and outcome variables. We put the significant variables from the bivariate analysis into a
series of stepwise, unconditional multivariate logistic regression and calculated the Odds Ratios with 95% confidence intervals (CI)
Int. J. Med. Sci. 2005 2
72
to assess the association between these variables and each of the following outcome measures: normal blood pressure,
prehypertensive status, Stage I and Stage II hypertensives status.
3. RESULTS
Total 1662 participants were screened. Of them, 53 (3.2%) persons did not want to participate in the survey. Thus the results of
1609 persons could be analyzed. Detail demographic data was given in Table 1 and the proportionate national data had been given
simultaneously. Our population showed slightly older than the national data. Total family screened was 526 (average adult persons
per family was 3.15).
Fig 1 shows the distribution of mean systolic and diastolic pressure in different age groups of the sample population among
both men and women.
Out of 1609 persons, Table 2 shows the distribution of different pressure range among various groups according to JNC-VII
criteria. Only 14.1% of the participants had normal blood pressure. A large number of participants could be categorized in
prehypertensive group. Overall prevalence of hypertension with a cut off mark of 140/90 mm of Hg is 24.9% (men and women). If
cut off mark is 165/95 mm of Hg, the overall prevalence stands at 8.5% (men -7.6% and women-9.6%). Of the hypertensives, only 3
percent individuals were on antihypertensive medications at the time of survey, and half of them had blood pressure within normal
range.
Fig 2 shows the influence of age and sex on distribution of both systolic and diastolic hypertension among the sample
population. In participants below 40 years, both systolic and diastolic hypertension showed higher prevalence in men. After 40
years, systolic hypertension showed progressive age-dependent increase up to eighth decade in both sexes and only in women, the
prevalence of diastolic hypertension remained higher up to eighth decade. Maximum prevalence of systolic hypertension was 64%

considered to be responsible for the higher prevalence of hypertension [17].
An analysis of mean systolic and diastolic pressures among Urban Indian population in the age range between 40-49 years
showed an increase of mean systolic pressure 120.4 mm Hg and mean diastolic pressure 73.2mm Hg in 1942 to 128.7 and 84.2 in
1985, 128.8 and 83.2 in 1995 to 141 and 85 in the present study [4]. Higher prevalence of hypertension is often indicated by a rise in
mean systolic and diastolic pressure. Similar observation has been noted in Yugoslavia and in Japan when it was a developing
nation and decrease in prevalence has also been noted in seven countries’ study along with decrease in mean systolic and diastolic
pressures [18].
Age related increase of hypertension is a common, but not a universal phenomenon. This is predominantly influenced by
environmental factors as certain non migrant or tribal populations, who follow a primitive life style do not develop age related rise of
prevalence of hypertension [19-21].
High prevalence of systolic hypertension at advanced age had been documented in few recently conducted surveys from India
such as from Parsi community in Western India (73% in age group equivalent to 70 years) [13], among Kerallite (51.8%) from
South India [12], Assamese (63.63% for people above 60 years of age) from North eastern India [22] and among elderly participants
from WHO sponsored multicenter study in Southeast Asia (65%) [3] as compared to an age specific prevalence rate of 64% in
seventh to eighth decade in the present study (Fig.2). Thus all the studies have recorded a high prevalence of hypertension. Systolic
Int. J. Med. Sci. 2005 2
73
hypertension has been considered to be one of the most important cause of morbidity and mortality leading to cerebrovascular
stroke, cardiovascular and renal diseases [23-24].
Influence of gender in hypertension prevalence has been observed among men who showed higher prevalence of both systolic
and diastolic hypertension in young age, but higher prevalence of diastolic hypertension in women after 40 years may be related to
increasing family stress and obesity which is common in middle aged woman [25].
The present study had shown a large proportion of sample population in the prehypertensive group. Table 2 has shown an
inverse relation between prevalence of prehypertension and age and the particularly victims were students and laborers. These
participants are of great interest since chance of progression to hypertension is high. Incidentally the previous study has shown
increasing prevalence of coronary artery disease among young in India [26]. The younger people in India are stressed out because of
heavy competition in academic fields and also for securing employment. Studies have already established that the relationship
between BP and risk of cardiovascular disease events is continuous, consistent and independent of other risk factors [5] and
prehypertensives have greater chance to go into hypertension [27]. Hence it is also possible that the young stressed individuals with
prehypertensives level of blood pressures may be at risk factor to develop ischemic heart disease. However no study from India

through, for example, practice of yoga. Our findings also suggest a protective role of non -vegetarian diet such as fish cooked in
mustard oil on hypertensives. Individually, both fish and the mustard oil are rich in unsaturated fatty acids, and biologically, their
beneficial effects are related not only to reduction of blood pressure, but also to lowering of lipids and to their antithrombotic effects
[28]. Useful role of fish cooked in mustard oil, as a protective factor needs to be probed further in future longitudinal studies.
Acknowledgement
We gratefully acknowledge the active help rendered by Apurba Chakraborty, Sumit Sarkar, Sujit Sarkar, Tridib Sanyal, Alok
Bhaduri, Malda English Bazar Municipality and the team of the councilors, Mr. Udayan Saraswati for computer assistance and the
people of Malda town for their co-operation. Our heartfelt thanks to Sonoscan- Malda for logistic support, and to Dr. M K Roy and
Dr. A Misra for reviewing the manuscript and useful suggestion.
Conflict of interest
The authors have declared that no conflict of interest exists.
References
1. Nissien A, Bothig S, Grenroth H, Lopez AD. Hypertension in developing countries. World Health Stat Q. 1988; 41: 141-154.
2. Reddy KS. Hypertension control in developing countries: generic issues. J Hum Hypertension. 1996; 10:S33-38.
3. Hypertension study group. Prevalence, awareness, treatment and control of hypertension among the elderly in Bangladesh and India: a
multicentre study. Bull World Health Organ. 2001; 79: 490-500.
4. Gupta R. Meta analysis of prevalence of hypertension in India. Indian Heart Journal 1997; 49: 43-48.
5. Chobanion AV, Bakris GL, Black HR. The seventh report of the joint national committee on prevention, detection, evaluation, and treatment
of high blood pressure- The JNC 7 report. JAMA. 2003; 289: 2560-2572.
6. Dutta BB. Studies on blood pressure, height, weight, chest and abdominal measurements of 2500 members of the Calcutta Police with short
notes on their medical impediments. Indian Med Gazette 1949; 84: 238-243
7. Washir HS, Ramchandran P, Nath LM. Prevalence of hypertension in a closed urban community. Indian Heart Journal 1984; 36: 250-253.
Int. J. Med. Sci. 2005 2
74
8. Hussain SA, Nayak KC, Gupta A. A study of prevalence of hypertension with reference to economic, educational, environmental and
hereditary factors in general population of North-West Rajasthan. Indian Heart Journal. 1988; 40:148-151.
9. Gupta R, Gupta S, Gupta VP, Prakash H. The prevalence and determinants of hypertension in the Urban population OF Jaipur in Western
India. J Hypertension 1995; 13: 1193-1200.
10. Anand MR. Epidemiology of hypertension. In: Anand MP, ed. Hypertension: an international monograph 2001. New Delhi: IJCP, 2001: 10-
25.

28. Lungershausen YK, Abbey M, Nestel PJ, et al. Reduction of blood pressure and plasma triglycerides by omega-3 fatty acids in treated
hypertensives. J Hypertens. 1994; 12:1041–1045.
29. Radack K, Deck C, Huster G. The effects of low doses of n-3 fatty acid supplementation on blood pressure in hypertensive subjects: a
randomized controlled trial. Arch Intern Med. 1991; 151:1173–1180.
30. Appel LJ, Miller ER III, Seidler AJ, et al. Does supplementation of diet with 'fish oil' reduce blood pressure? A meta-analysis of controlled
clinical trials. Arch Intern Med. 1993;153:1429–1438.
31. Rastogi T, Srinath Reddy K, Vaz M, et al. Diets rich in vegetables and use of mustard oil could contribute to the lower risk of IHD among
Indians. American Journal of Clinical Nutrition 2004; 79: 582-592.

Author biography
(continued from front page)
Kalyan Sanyal is currently working as a senior consultant physician in the Maldah District, West Bengal, India. Dr. Sanyal
completed his medical graduation in 1975, and his specialty training in Internal Medicine in 1985. He has well over 16 years of
experience as a consultant physician. His primary research interest is in neuroepidemiology.
Arindam Basu is the Assistant Director of the UC Berkeley (University of California at Berkeley, California) based Fogarty
International Training Program in Occupational and Environmental Health in India. He is both an otolaryngologist and an
epidemiologist. Dr. Basu graduated in the year 1990 from Medical College, Calcutta, India and had further graduate training in
otolaryngology and public health between 1993-1999. He had clinical and postgraduate training in medicine and public health from
Calcutta University, ESU, Pennsylvania, St. Louis University, Missouri, USA, and Washington University School of Medicine, St.
Louis. He returned to India in 2000, and continued to work as a consultant otolaryngologist and epidemiologist. In 2002, he joined
the UC Berkeley based Fogarty International Training Program in Environmental and Occupational health at the Institute of
Postgraduate Medical Education and Research as assistant director. His research interests include clinical outcomes research in
otolaryngology, clinical epidemiology, and environmental and occupational health.